Frank bell



(No Model.)

F. BELLQ oPERAToRS SEAT.

Patented Aug. 17,1897.

` tical section on line 3 3 of Fig. 2.

FRANK BELL, OF TUNBRIDGE VELLS, ENGLAND.

OPERATORS SEAT.

ESPECIFICATIGN forming part of Letters Patent No. 588,525, dated August17, 1897.

Application nea June 12, 1897.

To all whom it may concern:

Be it known that I, FRANK BELL, a subject of the Queen of England,residing at Tunbridge Wells, in England, have invented certain new anduseful Improvements in Operators Seats, of which the following is aspeciiication. f

This invention relates to an adjustable seat for the use of dentalsurgeons and others.

In the annexed drawings, Figure lis an elevation of the seat. Fig. 2 isa horizontal section on the line 2 2 of Fig. l. Fig. 3 is aver- Fig. etis a view of one of the parts carrying the seatpivot. Fig. 5 is a viewof said seat-pivot.

A is apillar having a base-plate A' and suitable webs A2 A2 A3, of whichthe former two -are more extended than t-he last.

A4 is a iiange on the pillar A about midway of its height, the upperface of this iiange having recesses in the form of ratchet or othervvteeth a. Above the 'flange A4 the diameter of the pillar A is reduced toform a spindle for a sleeve B, from one side of which there extends acurved or straight frame B", carrying at its outer end a vertical socketB2. Through lugs b on the sleevefB there passes a rod C, the lower endof which is adapted to engagethe recesses a, while the upper end isslotted to be engaged by the arm C of the lever C2, pivoted on thesleeve B. A spring C3 tends to press the rod C downward into engagementwith the recesses a, but such rod may be lifted out of-engagement withthe recesses by movement of the lever O2 by hand, thus leaving thesocket B free to be revolved on the pillar A., .The sleeve B is retainedon the pillar A by the washer D and flange of the screw D', screwed intothe upper end of the tubular pillar A.

There passes through the socket B2 the vertical limb of an L-shaped rodE. B3 is a setscrew having its outer end formed as a lever for turningit by hand to bear on the rod E after the latter has been adjustedvertically and rotarily;

F F represent a pair of blocks, of which each carries in the center apassage F, Fig. 4, (one of which is screw-threaded,) and below thelatter a transverse recess F2 and above SerialNo. 640,536. (No model.)

the passage F a vertical recess F3 with a groove F4. When such blocks FFare se- 4cured together by the screw G traversing the passages F', therecesses F2 form a socket for the horizontal arm of the rod E and therecesses F2 form a socket for holding the pivot AH of the seat J. ThepivotI-I has a ring H to engage the groove F4 in the recesses F2. Theblocks F thus, together with the screw G, form a clamp, which afteradjustment of the same upon the rod E and of the pivot H in the clampmay be tightenedy by the screw Gto firmly embrace the rod E and thepivot H and hold both with the requisite friction.

Having now described my invention, I claiml. A seat-supporting framecomprising in combination a vertical stationary pillar, a socketrotarily movable thereon, a frame extended laterally from said socket, avertical socket in the outer end of said frame, a rod having ahorizontal arm and a vertical arm the former engaging in saidlast-mentioned socket, a seat, a vertical pivot thereunder,

and a clamp adapted to engage said pivot and also the horizontal arm ofthe rod aforesaid, the whole substantially as setforth.

2. A seat-supporting frame comprising in Vcombination a vertical pillar,a base-plate thereto, a flange on said pillar having recesses in itsupper face, a sleeve rotarily mounted on the upper part of said pillarabove said flange,

a pawl on said sleeve adapted to engage the recesses in said flange, ahand-lever for disengaging said pawl, a frame extending later- -allyfromsaid sleeve, a vertical socket in the

